package com.dcy.facade;

/**
 * @Author：dcy
 * @Description:
 * @Date: 2021/1/22 10:31
 */
public class Screen {
    private static Screen screen = new Screen();

    private Screen() {

    }

    public static Screen getInstance() {
        return screen;
    }

    public void up() {
        System.out.println(" screen up");
    }

    public void down() {
        System.out.println(" screen down");
    }

}
